Clutch for power feed



Nov. 10 ,1925. 1,560,776

A. -.1. GIFFORD ET AL CLUTCH FOR POWER FEED Filed not, so, 1922 5 sheets-sheet l A/bwf J. f//om/ @y Wav-W6, BnJ'a/Tna'h 6.7.' Bishop Nov. 10, 1925l A. .L GlFFoRD ET A1.

CLUTCH FOR POWER FEED Filed Oct. 50, 1922 3 Sheets-Sheet .l2`

QT? Bava/gyn op l Novo lo,

A. J. GIFFORD ET AL CLUTCH FOR POWER FEED File opt. 30, 1922 3 sheets-sheet s www Patented Nov. I, 1925.

UNITED. STATES PATENT OFFICE.

ALBERT J'. GIFFORD, OF SHREWSBURY, AND BENJAMIN S. T. BISHOP, 0F WORCESTER,

MASSACHUSETTS, ASSIGNORS TO MASSACHUSETTS.

LELAND-GIFFOED coMPaNY, A conr'ona'rlon 0E U CLUTCH Eon POWER FEED.

Application led October 30, 1922. Serial No. 597,717.

To all whom t muy concern.'

Be it known that we, ALBEn'r J Grrronn and BENJAMIN S. T. BIsHor7 citizens of the United States, respectively residing at Shrewsbury and vorcesteiz in the county of Worcester and State ot' Massachusetts.

.have invented a new and useful Clutch for Power Feed, of which the lfollowing is a specification. I

This invention relates to improvements in the means for operating and lcoutrohiing a clutch to be used on a power feeding device for drilling. reaming, tapping, boring or other operations.

The principal objects of the inventionare to provide means associated with the clutch through which power is transmitted to the tool shaft by whicl1,'wl1en the clutch is operated to connect the power feed with the tool shaft, automatic means will be actuated thereby to hold the clutch in by spring pressure -as long as conditions remain the same and the tool is being fed into the work and until the depth gauge or Ilimitstop acts to throw the clutch out and also acting to hold the clutch out thereafter and being arranged to be automatically set either in the drivlng or non-driving position; and :furthermore to provide means whereby when the clutch is not to be thrown in automatically byv the engagement of the tool with the Work as is necessary with some kinds ot materials and Home kinds of operations, the device can be set so that at the time .when the tool comes into a posit-ion to engage the Work the clutch will be automatically actuated and to prof vide this in a form in which it can bev adjusted to provide for insuring this action taking place at any pointin the path through which the toolv travels toward the work.

The invention also involves further improveinents in the details ot construction and combinations of parts associated with Reference is to be had to the accompany ing drawings, in which- Fig. l is a'f-ront elevation of a part of a -gaged; .and

Fig. 16 is a similar View showing 'thel drill with a preferred embodiment of this invention applied thereto; Fig. 2 is a side view to show the interior construction; c

Fig. 3 is a horizontal sectional view through the center of ythe shaft which directly drives the feed rack. .F ig. 4 is a face View of the clutch, similar to a portion of Fig. 2;

Fig. 5 is an edge view of the clutch ring with vparts in section;

Fig. 6 is a sectional view-of theclutch l taken justV beyond the edge of the clutch ring, as indicated bythe ends of the arrows 6, 6 in Fig. 5;

Fig. 7 is a horizontal central sectional View showingthe clutch means in elevation; Fig. 8 is a sectional view of the same on the l1ne8`8 of Fig. 7;

Fig. 9 is a view similar to Fig. 7 showing another form of that part of the invention; Fig. 10 is a view similar .to Fig. 2 of a modilication. Y

Figs. 11 and 12 are enlarged views showing the positive limit stop in two positions when the tool spindle is at its highest point,v

as shown in Fig. l, and at its lowestpoint,v

as shown in Fig. 13, respectively; Fig. 13 is a View similar to Fig. 1 showing the spindle down; i

Fig. 14 is a central sectional view with the parts in the position shown in- Fig. 15;

Fig. 15 is a front view showing the position of the parts when .the clutch is rdisenclutch engaged and also illustrating the position of the depth gauge when the clutch is engaged but `about to be thrown ont.

Although this invention is capable of general use, we have shown only one machine to which it canbe applied, namely a sensitive drill. In order to show its connection with partly broken 'away this machine and thus-illustrate its use in general it maybe stated that the drill frame 10 is provided with a work table 114 for the workl 12 to be drilled or l on which other operations are to be performed. On the upper part of the trame are verticalA ways 13 on which travels a slide 14 carrying the tool ary bushing which supports a horizontal clutch.

ing aworm Wheel 22 constituting the driving element and located in a casing 23 which casingl is a part of the slide and as far as rotation goes is stationary. Rotatably mounted on the edge of the casing .'23 is av v .'depth ring 19 having acircumferential scale v and provided with thumb nuts and bolts 17 for securing it to the spider 30.

The worm wheel 22 is provided with a cylindrical hub which rotates on a stationshaft 25 constituting the element driven by the clutch. This worm wheelis cut out on its face to provide a flat circular space on one side in the outer edge of whichis fixed a ring 26. kThe worm wheel 22 may be of hard bronze or other convenient material but the. ring .26, which is fixed te it so as to constitute a solid part of it, is of. steel to take the wear as will appear. The interior of this ring 26 preferably is cylindrical and constitutes the wearing thrust surface of the Fixed on the shaft 25 is a disc 27 having a plurality of slanting' cam or wedge surfaces 28 spaced from each other. They are all rounded atthe end to receive a plurality of clutch rolls 29. These clutch rolls aremoved back and forth into and out of clutching position between the slanting surfaces on the disc 27 -and thecylindrical surface of the wheel ring 26 by a loose spider .30.V This spider has pro'ections 3l extend-l ing betweenl each two a jacent rolls and a slight turn in one direction will force the rolls up the inclines and cause the clutch to grip while alittle turn -in lthe other direction will release the clutch. yAs so far described,

y this is a clutch of the lclass known. as the I-Iorton clutch. A

On the spider 30'is a handle,'or preferably a pair of handles 32 for turning the spider. The shaft'25 near the other end has a spur geared meshing with a rack 34 carrying withln 1t the quill 9 and tool spindle 15 and .feeding them directly. Beyond this gear 33 1s a flat coiled spring 18 with one end fixed l to the shaft 25 and the other to the stationar bushing 24:.` rThis spring resists the lowering of the tool. This is shown more simply in Fig. 9. It will be understood that the spindle 15v is rotated in an independent Wely not shown herein.

n order to feed the tool spindle 15 down,

` the handles 32 are rotated and the tool will then be fed forward toward the work or yaway from it as desired. In order to provide for automatically connecting the clutch with the shaft 25 sov that after moving the latter by hand through the handles 32. until the tool touches the work, or meets resistring, will come into contact with either arm Y of they depth gauge 35 that is located m the way of it and as it comes around it will swing that arm back against a stop 37. If Aonly one arin -is used that arm is made wide enough so that the device will have to stop the first time the lpin 36 engages the depth gauge but two arms are shown located originally in the dotted line position where the upper arm enga-ges another stop 38.A Now the first time the pin 36 comes around it engages the lower arm of the depth gauge and swings it over into the fulllineposition in Fig. 2 but has no other effect except that the other arm of the depth gauge is left pro- -jecting out, as shown in full lines. Now,

the device can be rotated a complete revolution beyond that and then the pin 236 will engage the -depth gauge and the latter will act as a positive stop.

For the purpose of operating this in this way the ring 19v is provided with a circular scale, as shown in'F ig. 1, calibrated in the equivalents of inches of vertical motion of the quill. The casing 23 on which it is mounted is provided with a zero point. lVhen'the machine is to be started, the zero yon the scale is brought to the zero point and then the ring 19 is turned clockwise laway from it until the desired point on the scale registers with the zero point. This moves lthe pin 36 back and the scale shows how .many inches and fractions of an inch the vshaft 15 will be moved downwardly by the power before the device is stopped automatically. l y

On. the quill 9 is a stop 4.0, the upward mot-ion of which is limited by a pair of nuts 60 adjustable on a stationary screw 61.

In order to avoid chance of accidentally feeding the stop 40 on the quill 9 down positively against the bearing 41 (see Fig. 13)

which is stationary, thus injuring the machine, a positive limit stop L12 lis provided.

This works similarly to the depth gauge but is not adjustable.

lll)

three arms instead of two. In that case the spider 30 will rotate two and a fraction rotations betore it stops.

After the clutch is connected so af to drive the shaftby power it is desirable that it should not be autoinatit-ally disconnected in any accidental way and for this purpose we provide on the clutch spider 30 a lever 4l having a transverse edgre 45 with a slanting surface on each side ot it and pi'cssedby asprinze' -lt into contact with a triangular pin 47 located on the disc 27. Now, when the tool lo is moved down into contact with the work b v rotating the handle 252 and shaft 25 the contact of the tool with the work provides a resistance against the further rotation ot the shaft. Thev operator` however, continues to turn the handle and that causes a relative rotation between two parts that have been rotating together before, namely the shaft 25 and the clutch spider 30. The

4shai't- 25, which has been rotating without lost motion with the clutch spider, no w stops and the clutch spider continues to rotate a slight degree forcing the 'rolls up the inrlines, as stated and thus ii'onnectiiig the clutch to transmit rotation by power from the worin wheel 22 and ring` 2G to the disc 27 and sha-tt This also causes a relative rotation between the triangular pin 47 and the lever llt and forces the latter over the pin to the position shown in Fig. G.' Therefore, in order to disconnectthe clutch again` it is necessary to overcome the resistance due to the slanting cont-act surtaces of the parts 45 and 47 land the resistance of the spring 46. Now` when the hole is drilled to the desired depth and the pin 36 coinesto a stop against. the teptli gauge 235 there will again be a relative rotation between the shaft 25 and the clutch spider 3 0 in the opposite direction and thatl will cause a relative motion of the parts t5 and 47 in the opposite direction and force the pin over the tip of the point 45, the spring 46 yielding to permit this action to take place. Just as this occurs the i several projections 31 engage the respective rolls 29 from behind them and loosen the vrolls from the position in which they are carrying;rv 'the rolls 29 into the rounded or bottom surfacesof the wedges 28. At this time the lever L14 also moves over so as to carry its. edge 45 clear over the pin 17 to its extreme position. This now holds the rolls safely out of active position Then the f clock spring 18 ret-urns the spindle to its elevated position while the clutch is in that condition. l

lVhen drilling wood or aluminum oi other soft material and when reaming, or' performing some other operations which require comparatively little power, the 'contact ot vthe tool with the work will not produce suffi-- the spring .18 can be fixed to the cone. Fitting on the outside ot this cone is an internal conical bushing 5t. The shaft is provided with a screw thread 54 projecting beyond the/bushing 53 and on this is a holding nut The bushing 53 has-an offset portion in which isa spring pressed pin`56 having an inclined pointed end 57. yGn the frame there is a fixed pin 58 on the path of this en lThis bushing 53 is loosened afnd'vturned to any desired position around the,l circumference so as to provide the necessary rotation before the tool spindle`15 is connected with the power. Then the nut is tightened up and thereafter thebushing 53 will rotate with the shaft until the pointed end 57 comes in contact withthe pin 58, as shown in Fig. 8. This-then tends to stop the. rotation of the shaft 25 and puts the necessary resistance-on the same, asin the ease-described above, to connect the clutch automatically. Then the shaft 25 will be rotated by power and the tool driven into the work positively. Onv account of the pin 56 being spring-pressed, the end 57 will pass on beyond the pin 58 when the shaftI operates by power and will engage it again at each rotation but without effect.

In the form shown in Fig. J this feature is simply omitted.

It will be seen that the application of this invention to the i'orm of clutch illustrated herein or to any other form of a similar type provides for the holdine' of the clutch locked in clutched positionatter it is moved thereto by either rot' the means described.

lVhen the clutch is unelutched it` holds it in its unclutched position also. This'de-V pends upon spring-pressure and therefore is capable of being overcome bythe use of enough force but will not be overcome by the ordinary {iiictuations in power required for the operation being performed.-` The depth gauge acts in cooperation therewith to stop the machine and release thecliiteh at a predetermined time and at that time the holding device necessarily acts tohold thev elutchopen. Furthermore, the '-device can be set so that the tool will be'connected automatically with the power at any desired point in its travel without depending upon the resista-nce of the work.

-Although We have illustrated and described the invention as applied to a certain type of a machine tool and certain type of clutch, and shown only two forms of the invention, We`are aware of the fact that it Y can 'be applied to other tools and other the claims.

vsimilar edge for cooperating with the pin,

one of the last named elements being mountedto move with the driven element and the other With the spider, and yielding means for holding said two angular edges in contact at one side of the apex thereof but permitting them to be forced by each other upon the application of sufficient force.

2. In a clutch, the combination with the driving and driven elements, a spring for moving the driven element backwardly, a series of rollers for connecting them, and a clutch spider for moving said rollers cir- A cumferentially in either direction to connect or disconnect said elements, of a spring .pressed lever pivoted on the spider andvha'v- -ing a pointed edge, a pin fixed with re spectto the shaft having an oppositely pointed edge for holdinfr the lever, and therefore the spider, in eitlaierits set or open position. Y

3. In a feed mechanism,A the combination with the driving andA driven elements, aA Ispring for moving the driven element back- Wardly, a series of rollers for connecting them, and a clutch spider for moving said rollers circuniferentially in either direction to connect or disconnect said elements, of

a spring pressed lever pivoted on the spider and having a pointed edge, a pin fixed With respect to the shaft having an oppositely pointed edge for holding the lever, and therefore the'spider, in either its setv or ope-n osition, a casing in which the clutch is oeated,-a.depthl ring having a circumferA ential scale thereon provided with va pin,

and a depth gauge pivoted on the casing in position to be engaged bythe 'pin to throw the clntcli open. v

4. In a feed mechanism, the combination with the driving ,and driven elements, a

series ,of rollers for connecting them, and

-a clutchspider for moving said rollers in either. direction to connect or. disconnect 'said elements, of af .spring pressed lever pivoted oii the spider and having a trian- 'gular end, a triangular pin fixed with respect to the shaft for holding the lever, in either position, a casing in wliichsaid clutch is located, a depth gauge pivoted in the casing, and a depth ring adjustably carried by the spider having means for actuating the gleph gauge at any desired dept-hte stop the 5. In a feed mechanism, the combination with the driving .and driven elements, a

series ot'rollers for connecting them, and a clutch spider for moving said rollers in either directionto connect or disconnect said elements, of a spring pressed lever pivoted on the spider and having a triangular end, a triangulai" pin tixed with respect to the driven element for holding the lever in either position, a casing in which said clutch is located, a depth gauge pivoted in the casing, a depth ring adjustably carried by the spider having means for actuating the depth -gaugeat any desired depth, a limit stop in on the cone, a spring pressed pin on the bushing having a slanting end, and a fixed pin in the path of said slanting end for rcsisting the rotation lof thedriven elenien and setting the clutch. Y f

.7. In a clutch, tl'ie combination with the. driving'and vdriven element, a series of rollersl for connecting them, and a clutch spider for moving said rollers in either direction to connect or disconnect said elements, of a spring pressed lever pivoted on Vthe spider and having a pin viixed with respect to the shaft for holding the lever and circuiiiferentially adjustable means connected with the driven element for applying a resistance to its rotation after it has operated a predetermined time and releasing the clntcli` 8. The combination With a driving and a driven element, a seriesof rollers for con.

nect or disconnect said elements, of circuin- .fferentially adjustable means connected with the driven element for applying a resistance to its rotation after it has operated a presaid rollers in either direction to connect or disconnect said element, of a cone fixed on the driven element, an internal conical bushing fitting the cone and rota-table thereon, ineans`for fixing the bushing or. the cone, a spring pressed pin on the lbushing having l a slanting end, and a fixed pin in the path of said slanting end for resisting the rotation of the driven element and setting the clutch.

In testimony whereof we have affixed our signatures. ALBERT J. GIFF ORD.

BENJAMlN S. T. BISHOP..

10 hereunto 

